668960409 has 16 divisors (see below), whose sum is σ = 962424512. Its totient is φ = 410868288.

The previous prime is 668960399. The next prime is 668960419. The reversal of 668960409 is 904069866.

It is an interprime number because it is at equal distance from previous prime (668960399) and next prime (668960419).

It is not a de Polignac number, because 668960409 - 2⁸ = 668960153 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (668960419) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3999 + ... + 36795.

It is an arithmetic number, because the mean of its divisors is an integer number (60151532).

Almost surely, 2^668960409 is an apocalyptic number.

It is an amenable number.

668960409 is a deficient number, since it is larger than the sum of its proper divisors (293464103).

668960409 is a wasteful number, since it uses less digits than its factorization.

668960409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33336.

The product of its (nonzero) digits is 559872, while the sum is 48.

The square root of 668960409 is about 25864.2689631855. The cubic root of 668960409 is about 874.5812021422.

The spelling of 668960409 in words is "six hundred sixty-eight million, nine hundred sixty thousand, four hundred nine".